Luggage cases conventionally include supports, such as wheels, attached to the case to allow the case to stand on or be transported over a support surface easily during use. The supports are attached at or near the bottom of the luggage case support structure.
The supports on a luggage case are typically positioned at or near the perimeter of the bottom side wall, near the corners. The supports are mounted at or near the perimeter to provide a base having as large of an area between the supports as possible, for stability purposes. In particular, the depth dimension between the supports positioned at the front and rear edges of the bottom wall, respectively, helps determine the stability of the luggage case. This depth dimension in relation to the depth dimension of the luggage case at a location midway along the height of the luggage case largely determines whether the luggage case is stable when loaded with contents. In some conventional luggage cases, the bottom side, as well as the dimension between front and rear supports, is smaller in the depth dimension than the depth at a location midway along the height of the luggage case.
An identified problem with the conventional support location scheme is that many luggage cases may be loaded in a manner that causes instability, either by an off-center loading of the luggage case, or where the front wall extends outwardly to define a depth dimension greater than that of the supports, and thus extends beyond the location of the front supports. This can cause instability, and possibly result in the luggage case tipping over either when at rest or during transport. Using a pocket on the front wall of a luggage case, or an expandable feature on the front wall may concentrate the load at that lateral location causing the instability.
Some conventional luggage cases taper from a lesser depth dimension at a top portion to a greater depth dimension at a base. In the event this style of case tips over onto its front panel, the front panel engages the support surface along all or a majority of its length. These conventional cases, aside from having reduced packing volumes, lack a protective feature to lessen the impact and negative effect of such an occurrence, and specifically related to the lower region of the front panel and any zipper or other closure feature that may extend across the lower front portion of the front side.
Additionally, some convention luggage cases improve stability by using supports that are designed to extend beyond the perimeter of the bottom side of the luggage case, thereby increasing depth, and thus the stability. These extended supports may be structurally less sound than supports mounted more integrally with the luggage case, and also increase the outer most peripheral dimension of the luggage case without improving its packing volume.
It is therefore desirable to provide an improved luggage article, and more specifically an improved luggage case main structure, that addresses the above-described problems and/or which more generally offers improvements or an alternative to existing arrangements.
Documents that may be related to the present disclosure in that they include various means of defining the location of the supports are:
EP1718183; CN2342662Y; U.S. Pat. No. 590,893; US2011/0120828; (TW) D14465251; U.S. Pat. No. 5,423,561; U.S. Pat. No. 5,230,408; U.S. Pat. No. 6,419,198; U.S. Pat. No. 3,923,318; U.S. Pat. No. 3,871,676; U.S. Pat. No. 3,964,762; U.S. Pat. No. 3,734,527; US2013/0032558; U.S. Pat. No. 5,890,570; OHIM001770777-0001; EP0106906; EP0900031; and WO97/31550.